5. Delete the row added in the previous step from Price table using Delete from (not rollback).

Q18-Q20 require using data dictionary items. Use one SQL for each.
18. Find all check constraints defined on emp. In the result, list name of the constraint.)
19. Find all tables in your account. Return the table names as output.
20. Find all foreign key constraints defined on emp table and on dept table. In the list, list the name of the constraint and which table it is defined on. USE only one SQL statement to accomplish this.)